: Our usual technique for injectables in my office is about as John describes,
: given that we've got rigid containers for all the stuff we use
: (anesthetics, etc.). However, from the soft picnic bottles, a coordinated
: and lucky person can, with practice, draw up in one go, squeezing the
: container just enough to minimize the vacuum from becoming much of a
: factor; after all, it's going to break when you separate the syringe from
: the bottle. Doing this, you can draw avoid getting air into the syringe as
: you're drawing up and having to let it settle out.

: Alternative: Keep amounts of resin and hardener in glass jars such as the
: peanut-butter variety; use the catheter-tipped syringes to draw up while
: you easily see that the tip is just barely in the liquid, minimizing mess
: much more manageably!

: Just a thought--

: Craig

Hmmmmm!! I think some of us are missing the point here. With the oral syringes, you don't draw up anything. You put the syringe in the bottle top, turn it over, draw back the plunger, usually beyond what you want, then push it back to your measure, turn the bottle upright and pull out the syringe. It won't leak as there is a vacume created in the syringe to hold it in place and no leaks from the bottle as it's upright and all the resin is down where it belongs. It can't be simpler. ?? I don't know from Catheters and needles and such but I'm sure they take a long time to feed resin through with such a small hole. The orals have a 1/8" to 3/16" hole and draw it in a second. And since this in ONLY used to measure out material that will go into another cantainer to be mixed, I don't think there's any reason to go with anything too technical.
Since the bottles are soft, I have had no problems with any type of vacume issue. The bottle sides just move in a tad and when you turn it over and remove the syringe, the air pops back in.... like magic. On the first set I made, I got some harder plastic bottles and when I would draw the resin down into the syringe, I could see air bubbles seeping in around the cap and bottle neck. But, no resin ever leaked out. Hope this helps!!

Rehd